Setting the Construction Priorities of the Routes in a Common Duct Network

Constructing a full scale common duct network (CDN) requires considerable budget support. In reality, a CDN is constructed in distinct phases rather than in a single phase because of budgetary limitations and other related factors. How to prioritize the route construction of a CDN is thus a crucial issue for the authorities. This study derives the critical variables for determining the construction priorities of routes in a CDN using expert interviews and questionnaire surveys. Statistical analysis is also performed to check the validation and verification of the survey results. Moreover, factor analysis is used to derive 24 priority determinant variables and classify them into five groups, including utility agency, traffic condition, local government, infrastructure project, and site condition. An evaluation model is developed herein to rank the construction priority of the routes in a CDN. The pairwise comparison method is then used for weighting the five groups. The site condition is found to be less important than other factors in determining route construction priorities for a CDN. Finally, a six-route CDN located in northern Taiwan is analyzed using the proposed model, and the analytical results are objective because of the consideration of multiple viewpoints.